How deep does the camera “see”?
Thermal imaging can only see the surface of the skin, however the autonomic nervous system controls the blood flow to the skin and so this will reflect the state of the tissues under the skin. So, while saying that “thermography only sees the first millimeters of depth” is technically true, it misses the physiological response that controls the temperature at the surface. Just as someone’s turning red with embarrassment is an autonomic response to an emotional reaction, the changes seen with thermography are an autonomic response to the tissues underneath. So, the surface heat patterns do show what’s going on underneath.
